314 



♦ KNOWLEDGE ♦ 



[August 2, 1886. 



classes. The following description will suggest the amount 

 of material and labour on one of the ventilators : — One 

 l(5-iuch diameter 'Boyle's Patent Self-acting Air-Pump 

 Ventilator,' made of galvanised iron and painted; Ih foot 

 of S-iiich pipe, with dividing plate ; 30 feet of 5-inch 

 diameter pipe, 8 feet of 4-inch pipe, two 5-inch junctions, 

 two 5-inch knees, two 5-inch Ganges, two 4-inch junctions, 

 two 4-inch knees; four air-inlet brackets, 10 inches by 

 5 inches bv 3 inches. When it is said that all the above 

 will be made of strong galvanised iron, and will cost only 

 four guineas complete, it will be plain that there is no 

 charge for anything beyond the net cost of materials and 

 workmanship. A plan and printed instructions are supplied 

 along with each set of appliances. The system can be 

 applied to tenements at the same rates, every room in the 

 largest block being ventilated separately. It can also he 

 applied to existing buildings at a trijlimj extra expense. 



It thus appears that one need not be at a loss nowadays 

 to ventilate a room or a house perfectly and at a small 

 cost. But to return to the subject of admission of fresh 

 ail- into the room. It should be freed from particles of 

 dust and dirt, should not cause a draught, and should be 

 capable of being warmed or cooled at pleasure. All these 

 desiderata are found combined in many of the inlet venti- 

 lators now in the market, such as those of ilessi-s. Boyle, 

 Lamb, Ellison, and others, and may be adjusted by any 

 ordinary workman with ease. With inlet ventilators one 

 should be careful to select such a position in the apartment 

 as to enable it to work in conjunction with the outlet, and 

 it is in addition advisable to supplement it by adding a 

 closable ventilator to each window, as in Verity's Miiltuni 

 in parvo window, where ventilation of the room is assisted 

 by a frame which gives a maximum of light, is burglar and 

 weather proof, and, since it can be turned completely round, 

 may be cleansed from within the room. All these things 

 taken together point it out as the window par excellence for 

 the naturalist's laboratory. 



Another thing of importance about the structure of the 

 student's room is that the doors should fit so well as to 

 prevent the incursion of dust particles. Now, nearly every 

 door is apt to warp or the threshold to wear away, so that 

 in time a patent space remains beneath through which 

 quantities of dust may enter. This may be prevented by 

 alfixing to the base of the door an appliance chilled " War- 

 hurst's Automatic Dust, Draught, or Eain Excluder." It 

 consists of a movable pad, which rises when the door is 

 opened, and is depressed upon the closure of the latter in 

 such a way as to give perfect contact everywhere with worn, 

 wearing, or uneven thresholds. 



By Richard A. Proctor. 



It has been our wish, since Knowledge was started in 

 1881, to give readers more than any other magazine of the 

 same nature has supplied at the same price, and also to 

 make an opening for original interpreters of science on 

 fair, or lather on generous terms. We knew well that 

 competition with the story-telling magazines, which ensure 

 a wide circulation by serial novels or by short narratives, 

 would bs useless, so that we could not hope to compare 

 columns with the Cornhill, Longmans, and similar maga- 

 zines. Nor, on the other hand, did we expect to provide 

 the' same amount of material per shilling as the English 

 Mechanic, and other similar magazines intended chiefly to 

 meet the special wants of large classes of working men. 

 But comparing with other journals which have the same 



general character or scope as this one — the Popular Science 

 Montldy in America, Xatiire in England, the Revue 

 d'Astronomie in France, itc. — we hoped to be able to give 

 more matter, and especially more original matter. Com- 

 paring even with such magazines as the Contemj)orarij 

 and the Xineteenth Century, we hoped to remain ahead in 

 this respect. 



So for, we have achieved our purpose, and (especially of 

 late) with growing support of an encouraging nature. But 

 it has been at the expense of making every number of 

 Knowledge more or less of a gift, and by allowing paid con- 

 tributions to be the only fully ])aid portion of our work. 

 Every week the editor has had to provide, by work outside 

 Knowledge, for the extra expenses which a too generous 

 system at starting had involved. After five yeai-s on these 

 lines, and finding the time still far oft' when our growing 

 constituency will pay the expenses of publication, we find it 

 desirable — nay, absolutely necessary — to take in sail, hojjiug 

 that the favouring breeze of popular support will not cease 

 therefore to waft our bark outwards. We still carry more 

 sail than other craft of the same class. For example, taking 

 those above-named in their order, the comparison will here- 

 after run thus (taking in aach case the supply of matter per 

 sixpence of prices) : — 



Poptdar Science Monthly 36 cols., averaging 500 words 

 Xature . . .48 cols., averaging 600 words 



llevtie d'Astronomie . 20 cols., averaging 450 words 

 XlXth Century it Con- T 



temporary Review, >36 cols., averaging 500 words 

 not illustrated, each . J 

 Knowledge, from now . 48 cols., averaging 700 words 



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We trust our readers will recognise the fact that 

 we have done and are still doing the best we can. 

 With regard to the scope and purpose of Knowledge, 

 we have an object far higher (to our thought) than the 

 mere interpretation or explanation of scientific matters. 

 This object is aimed at specially in such papera as those on 

 the Story of Creation, the Unknowable, and the like. But 

 for the opportunity of suggesting such teachings from 

 nature as are sought to be conveyed in these papers, Know- 

 ledge would not be continued at all. 27*6 great lesson which 

 the recent progress of science teacher is the universal prevalence 

 of law and the conseqiient futility of laidessness, no matter 

 under what high or seemingly sacred names it may he dis- 

 guised. This lesson we wish Knowledge consistently and 

 persistently to teach, for of all lessons yet taught mankind 

 this is the most valual)le. Other teachings in our pages are 

 but such accessories as have appeared desirable to secure the 

 stability of the .Journal from the publishing point of view. 

 Among these must be considered the cheapness at which we 

 formerly aimed. This we have to forego or rather to reduce. 

 The change has, indeed, been too long delayed, and would 

 have been made much earlier had we earlier had such full 

 information respecting expenses and proceeds as we obtain 

 under the present publishing arrangements. If our readers, 

 mistakenly supposing that we are dealing unfairly by them, 

 should desert us, Knowledge will simply cease to exist. 

 Should they, as we hope, stand by us, Knowledge will go 

 on without loss (at any rate) to the proprietors. Should 

 they, however, help to increase and extend the circulation of 

 our Journal, as they readily may, we shall hope to return 

 hereafter to our former dimensions. So long, however, 

 as that would involve a monthly loss, it would be folly to 

 continue the attempt. 



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